The present invention relates to a lock bypassing tool for operating, for example, the deadbolt of a mortise-cylinder lock without using the key designed for fitting the lock.
Opening locked doors by means other than the key designed for a particular lock is a service rendered frequently by licensed and bonded locksmiths when hired by the occupants of locked premises having lost or misplaced their key, or when called upon to open locked premises for the benefit of appropriate public safety officials having legitimate reasons for gaining access to the locked premises.
The apparition on the market of high security locking systems have caused conventional lock "picks" to become obsolete, and has given rise to a new generation of specialized unlocking tools, such as vibrating blade or movable rod tools, in attempts to provide alignment of the lock tumbler pins with the shear line between the lock plug and cylinder such as to enable the plug to be rotated relative to the cylinder. Because most security locks have portions made of case hardened steel, drilling out the lock, even with a masonry drill bit may be difficult, and always results in causing considerable, and often irrepairable damages to the lock, or even to the door, thus requiring replacement of the lock and repair of the damages.
In U.S. Pat. No. 4,339,863, there is disclosed a lock opening tool capable of operating the deadbolt of a mortise-type cylinder lock, after drilling out the plug to the relatively large diameter of the tool such as to permit insertion of the tool shank through the drilled out plug. The tool consists of a flexible steel blade disposed in an elongated tubular housing open at one end and closed at the other end where it is provided with a radial slot through which the end of the flexible blade projects at a 90.degree.-angle for engagement with the latch or bolt operating mechanism. Such a lock opening tool requires that a relatively large bore be drilled through the plug of the lock, and considerable difficulty may be encountered in attempting to operate the bolt with a length of relatively thin flexible steel blade.